The present invention relates to axles and differential drives for motor vehicles and more particularly, relates to an axle module with twin pull electronic torque management for use in a vehicle.
Torque distribution systems in automotive vehicles have been known for many years. Generally, torque distribution devices either control the torque being transferred to an axle as found in an in-line xe2x80x9chang-onxe2x80x9d all wheel drive system, or may even control the torque being transferred to each individual wheel, as found in a twin xe2x80x9chang-onxe2x80x9d all wheel drive system. In the twin xe2x80x9chang-onxe2x80x9d all wheel drive system there is typically a primary driven axle and a secondary driven xe2x80x9chang-onxe2x80x9d axle that is connected via prop shaft or drive shaft and torque transfer coupling to the primary driven axle. The primary driven axle also includes a differential which divides the torque to the side shaft of each axle and then to the wheels. The division of torque between the primary and secondary axles is controlled by the torque transfer coupling which is usually integrated in the secondary axle.
A typical prior art twin xe2x80x9chang-onxe2x80x9d all wheel drive system provides a permanent drive primary axle. However, when the primary axle starts to slip, i.e. the wheels are on a slick road condition or loose gravel, etc., the prior art systems apply torque to each wheel of the secondary axle until the appropriate wheel torque is achieved. This provides a traction performance advantage over in-line xe2x80x9chang-onxe2x80x9d torque distribution systems under slip conditions similar to that of a limited slip differential. It should be noted that the twin torque distribution systems eliminate any need for a differential gear set within the secondary axle.
However, with the increased traction performance of the prior art systems, a substantial number of drawbacks are encountered such as complexity of the torque distribution system, the weight of the torque distribution system and the cost to manufacture and design such systems. Furthermore, the prior art torque distribution systems generally have axles that are bulky and difficult to package in the small area left for the driveline systems. Also, the increased cross vehicle width of most twin axles causes the inboard side shaft joints to be positioned or shifted towards the wheel, thus leading to packaging conflicts with the chassis components and an increase in joint angles which effects the efficiency and durability of constant velocity joints and the like. In the recent past there have been numerous attempts to over come the above-identified problems in the area of conventional driveline systems. Most of these systems have tried to develop a method to reduce the mass, packaging requirements and joint angles of conventional axles by integrating the inboard side shaft joints and the differential housing. However, no such integration with a twin axle including speed sensing or electronically controlled clutch packs, have been provided to date.
Therefore, there is a need in the art for an axle module that includes an integration of joints into a smaller package, having reduced weight and lower side shaft joint angles within the torque distribution system that also still provides the improved traction performance demanded by all wheel drive systems. Furthermore, there is a need in the art for a torque distribution system that can electronically be controlled thus providing for tuning of each desired vehicles handling and performance requirements.
One object of the present invention is to provide an improved torque distribution system.
Another object of the present invention is to provide an integrated axle module that includes twin electronic torque management units.
Yet a further object of the present invention is to reduce the weight and packaging requirements for an axle module in an automotive vehicle.
Another object of the present invention is to provide a torque distribution system that electronically controls the tuning for the desired vehicle handling and performance requirements.
It is still a further object of the present invention to provided an axle module that is capable of twin axle preemptive locking measures.
It is still a further object of the present invention to provide a torque distribution system that is driven directly from the transmission.
To achieve the fore going objects the axle module for use in vehicle includes a housing. The housing has a ring gear assembly rotatably arranged within the housing. The axle module also includes a shaft arranged within the ring gear assembly. A clutch pack unit is arranged within the ring gear assembly of the axle module. The axle module also includes an expansion unit arranged adjacent to the shaft and the housing.
One advantage of the present invention is a new and improved torque distribution device for a vehicle.
A further advantage of the present invention is that the integrated axle module improves traction while reducing the weight and packaging requirements within the drivetrain system.
A further advantage of the present invention is that the axle module is capable of independently controlling each wheels distributed torque via a motor.
Another advantage of the present invention is that the integrated axle module can be tuned for the desired vehicles handling and performance requirements.
Yet a further advantage of the present invention is that the integrated axle module can be used as a preemptive blocking device for each axle and wheel independently of each other wheel.
Still a further advantage of the present invention is that the prop shaft is driven directly from the transmission thus removing the need for a torque transfer coupling.
Other objects, features and advantages of the present invention will become apparent from the subsequent description and the appended claims, taken in conjunction with the accompanying drawings.